No recovery after 40 years in experimental deep-sea mining tracks

In the 1970s and 1980s, several pilot mining experiments (DOMES, IOM BIE, DISCOL) scraped and removed polymetallic nodules from small patches of the abyssal seafloor to study environmental impacts. Researchers revisited these sites decades later -- most notably the DISCOL site in the Peru Basin after 26 years and the IOM BIE site in the CCZ after 40+ years. They found that biological communities had not recovered to pre-disturbance states: nodule-dependent species were absent (because the nodules themselves grow at rates of millimeters per million years and cannot regrow on human timescales), sediment fauna remained depleted, and community composition was fundamentally altered. This means that every square kilometer of seabed mined represents a functionally permanent loss of that ecosystem within any meaningful human or regulatory timeframe. The structural reason this problem is intractable is that abyssal ecosystems operate on geological timescales -- nutrient input is minimal, metabolic rates are extremely low, and the hard substrate (nodules) that many organisms depend on takes 10-15 million years to regrow to harvestable size.